Pressure-gage.



1. A. BOWDEN.

PRESSURE GAGEi APPLICATION FILED SEPT.1`2.1910."PPNEWD FEB. 2. i915.

l l 52,9?6. Patented Aug. 31, 1915.

S'UNIUS A. BOW'DEN, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO A. SCHRDERS SON, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

PRESSURE-enen.

Application tiled September 12 1910, Serial No. 581,673. Renewed February 2, 1915. Sierial No. 5,781.

To ali whom 'it may concern:

Be it known that L J'uiriUs A. BowDEN, a citizen of the United States, residing at Los Angeles, in thel county of Los Angeles and State of California7 have invented anew and useful PressureGage, 'of which the following is a specification.

This invention relates to pressure gages and particularly to one designed for deter-v mining the air pressure ina pneumatic tire.

in a previous application of mine, filed Sep' teinber 9, 1909, Serial No. 516,9153, I have shown and described a pressure gage of this 'type in which the air chamber is formed as an expansible rubber chamber. The present invention 'relates to an improved construction and embraces several novel features which maite the device more''serviceable ln pressure gages usedfor determining the pressure'in tires, it has heretofore been necessary to provide some means in .the gage for depressing the valve stem when the gage' was applied to the valve in order to let the air pass from the tire into the pressure gage',

one ot the objects of the present invention is to obviate the use ofsueh valve opening means, and accomplish this by producing a slow leak in the valve, so that when the pressure gage is applied to the valve, the

air which is leaking through the valve will pass into the to register the pressure, and when the cap ot the inlet nipple is removed will prevent escape of air in appreciable quantities and obviate employing a `check valve in the inlet nipple.

Another obiect of the invention is to 'provide novel and effective means for securing.

iliary to the rubber air chamber for restoring the latter to its normal volume. The` rubber air chamber is protected within a Vcasing through which the indicator bar is projected `when compressed air is admitted Fig. 9v is a perspective view of one of the.

to the gage, andV a further object is to seal the joint between the indicator bar and casing to prevent the entrance .of dust and Water.

Another object of `the invention is to elnninate the necessity. of a check valve in the nipple of the gage. lrVhen the regulation depresser is used the back How of air from the tire would rapidly escape during the interval of removing 'the cap of the inlet nippleand'attaching the air hose and again when removing the air hose and attachingl the cap to the inlet nipple. A very slow leak will soon fill the small space in the gage and equalize the pressure in thetire'and gage. Another advantage is that when the gage is secured to and maintained on the tire, should the gage become loosened, the leak will not allow the tire to become de- A further object is to provide a special fitting for securing the gage rigidly and permanently to the inlet tube of the tire and yet lenable the fitting to be detached therefrom when desired'.

The invention also embraces other advantages which will be brought out in the following` detailed description. .j

Referring'to the drawings: Figure 1 is a :vertical sectional view through the gage andfvalve to`which the gage is applied.

Figf a section on line r2-m2 of Fig. l. Fig. 3 v1s a .perspective of the band` which seals the Jolntjbetweemthe exterior casing vand indicator bar. Fig. Je is a perspective view in detail of the gage bar. Fig. 5 is a perspectiveview, inverted, in detail of the cap Afor the upper Aend of the rubber air chamber. Fig. 6 is a perspective view of the locking ring which locks the indicator bar to the rubber air chamber. Fig. 7 is a' perspective view or' the reverse side of the capshown in Fig. 5. Fig. Sis a perspective view in section of the rubber air chamber.

rings for maintainingthe lateral dimensions of the air chamber. Fig. 10 is a perspective View ofthe fitting or body portion 'of the gage. Fig. 11 is a perspective view in detail of the annular nut for securing the gage to the valve of the tire. Fig. 1Q is a perspective View in `detail of -the Washer which fits the flattened sides of the valve of the tire. Fig. 13 is a perspective View in detail of the coupling at the lower end of Patented fling. 31, 1915.

.Hated so quickly as where 'the regular dey presser is used.

eol

is'a perspective View of another split ring4 at the bottom'of the air chamber. Fig. 1

.is a perspective view of the inlet nipple.

A.air seal for the inlet nipple. lperspective view in detail ofthe pressure, f plate for the inlet nipple. Fig. 20 is a per- Fig. 18 is a perspective view in detail of the Fig. 19 is a f spective view of the cap for the-inlet nipple.`

1 designates the threaded nipple of the tire valve within which is the valve 2 of well known construction. In order to pro duce a slow leak in the valve, I remove the .rrubber which occupies the annular space 3 which permits the' air to pass slowly outward through the valve nipple 1. It should be understood that this rubber which is re- -moved is not the valve but the gasket which seats against the internal shoulder of the nipple 1. With this rubber gasket removed, air will slowly leak up past flange 2 and past the threaded portion of the valve into the passage 7.

4 designates the body portion of the gage which is formed with a lower threaded l flange 5 and an upper threaded flange 6 and with a longitudinal air passage 7. Screwed into the fitting at right angles thereto is an inlet nipple 8 which communicates with the air passage 7, the outer end of the nipple being closed by a cap 9 which bears against a pressure plate 10, the latter holding a rubber disk 11 against the end of the nipple and thereby rendering the same air-tight.

The pressure plate 10 is formed with a cen- I tral conical projection 12 against which the cap 9 bears and by means of which the v plate 10 bears with a uniform pressure throughout its entirearea against the disk 11, which insures a perfect fit preventing leakage of' air. By removing the cap 9 and plate 10 and disk 11, air may be pumped through the nipple 8 to inflate the tire, air entering freely through the valve along the valve stem in the well known manner. It should be understood that the air which enters in the regular manner through the valve necessarily passes through the space 3 as well as air which escapes by the slow leak. The slow leaking air however, does not pass along the valve stem but passes around the outer edge of the flange 2.

The lower end of the fitting 4 is enlarged to fit over the upper end of the valve nipple 1 and a rubber gasket 13 forms an airtight joint at this point. The fitting is secured to thevalve nipple by means of a sleeve 14 which is screwed to the lower flange 5, a s t screw 15 preventing the accidental unscrewing of the sleeve 14. The

sleeve 14 has a shoulder 16 against which rests a washer 17 having flattened sides 18 which fit the well known flattened surfaces of the valve nipple 1, so that the washer 17 is prevented from rotating. An annular nut 19 is screwed on the valve nipple 1 and 'the washer 17 abuts against the same, the parts being firmly secured together by screwing the fitting into the sleeve 14. The upper end of the fitting 4 is formed with a flanged `boss 21 externally grooved, and secured thereto is an expansible rubber air chamber 22, the latter being cylindrical in form and entirely closed except at its lower end, at which point it is formed with an inwardly directed flange 23 which fits under the flange of the boss 21 and is secured thereto by two split rings 24 and 25. The inner ring 24 is first placed in position, then the outer ring 25 is placed over the inner ring 24, the joints of the rings being out of line with each other. The outer ring 25 has an upper beveled edge 26 and after the two rings 24 and 25 are in position, a casing 27 is pushed down over the outer ring 25. It will be noted that the lower portion of the casing 27 acts in the capacity of an encircling ring or band to crowd the split ring 25 tightly against the split ring 24 and cause the latter to compress the lower end of the rubber air chalnber 22 into the closest possible union with the flanged boss 21 and thereby prevent leakage at this point and at the same time mechanically secure the'rubber air chamber 22I to the fitting 4 in such a manner that it can not come off. By tapering the upper edge of the outer ring 25, it is possible to force the casing 27 into position. This method of securing the air chamber to the fitting is particularly effective, considering the small space afforded for the securing means.

The lower end of the casing 27 is provided with a flange 28 which abuts against the flange (5 and a flanged nut 29 engages r the flange 2S and holds the casing 27 firmly in position. When thus secured, it is obvious that the lower end of the rubber air chamber 22 is prevented from expanding and therefore its inwardly directed flange 23 cannot possible become disengaged from the flanged boss 21.

Secured to the upper end of the air chamber 22 is an indicator bar 30, the lower end of which is formed with a flange 31, the upper face of' which is formed with annular grooves A neck 33 is formed between the indicator bar 30 and the flange 31, thus leaving a shoulder 34. The flange 31 is received in a pocket 35 formed in the upper portion of the air chamber, there being an. orifice 36 through the upper wall giving comn'iunication with the pocket, but the pocket 35 has no communication with the interior of the air chamber. The flange 31 is diameter which ii t'- inname Jed through the hole 36 by stretching t rubber end after the iienge 3l is received in the pocket 35, `the .upper wall closes around the neck 33 ofthe indicator bar, shown in Figa '1., A cap 37 is then placed 1 upper end o'f the air chamber, the having an orifice through which indicator bar loosely passes, showvn isr i end then a split locking ring 39 is e1" "-9 l eed over the neck 33 above the cup 3l takes against the .shoulder 3i thereby securely holding the cap 3? in place, which prevents the upper Wall ofA the air chamber troni pulling outwardly. The inner bottom wall of the' cap 37 is also formedivi th concentric corrugations t0 which, combined ith the corrugations 32, grip the rubber dining the top wail of the air chamber on h. and. thereby assist in the more securing` tlie`indicator bar in position. n order to prevent the air chamber i'r'oni efnuifoding;laterally,V encircle it with wire. l ferebiy, i employ a plura-lityloi" wire rings 31'S one of which is. shown in detail ni 9., Each ring 3l .is endless and thus no chance ci' puncturingthe rubber. ifheso' rings 'are spaced apart a suiiicient dis- V'nice to retain the air chamber to its lateral d' ensicns and' yet aliovv it to elongate longitndinaiiy when 'the air under pressure is, admitu d to its interior.

l fi the casing 2! isa coil spring); il which beurs agionst 'the cap 37 and serves to in restoring; the air cliamber to its norn'iai condition. The spring i-ll also adds its resisten to that ailiiorded by the rubber walis ol'v the air chaln'iber, so that While the air chamber is depended upon for the air storage and acts as an airtight pocket in communication 4with the tire to retain 'the air und expand under the air pressure, the resistance to such expansion isaiiorded only :in Dart by the rebbe1 air chamber, the spring' 112i acting in conjunction therewith. .A

in order to prevent the entrance of dust or water the upper end of the casing' 27, einpioy' a rubber collar i2 which is clasped tightly over the upper end of the casing and snugly :lits 'the indicator bar 30. Y'he rubber n'icrnber 42 at 'the top has a normal is i smallest dian'ietcr as shown in contact v ,Y the scale bar, vvhiie 'that portion which is stretched engages the casing"n yThus the smaller diameter' oil" the rubber does not tend to grip the scale bar tightly enough to produce friction which would materially retard the movement of the scale bar. The indicator bar 530 is pro- `vided with graduations 43 'which are exposed to view es the indicator bar is moved out during' it should be understood that one oi"l 'these devices is applied to the air valve of'each the expansion of 'the air cimmtire and remains there permanei'itly, being at all times in communication ivith 'the air pressure within the tire by reason ot the sloiv. air .leak provided, and thus the indicater bar will always protrude from the casing and indicate the exact pressure which is within the tire, so that a glance sufiices to tell whether the tire needs inflat ing)- or not. Wheninllation is-needed.l a siniplo matter to' reniox e the cap 9 und ine 'late through the inlet nipple What I claim, is: f

ll. in a pressure ,Qage a longitf'idinally eX- pansible cyiixulrical rubber air chamber iin.- lperforate except at its inner und. the longitudinal walls oiA said chamber being straight and coils of .vire surrouinling the chamber, preventing it from expanding laterally, an indicator bar bearing' against the outer end of said chamber, the outcrn'iost coil oi" wire lying' at chamber, a retarding spring havin,r one end bearing' against the top o'l,t said chamber,

it isv a point near the outer end of said means supporting 'the other end oi' thev ben said air chamber having' a pocket 'in one end, an iinlicator bar having a lann'e on its end 'which is seated in sai( pocket, and means for holding' the upper wall oi said pocket against said flange.

S In a pressure eager a rubber air chainber, said air chan'lber having a pocket in onen cud7 and an indicator bar having" a ilangc on its end which 1s seated 1n said pocket.l

Li. in a` rn'essure grillige` a fitting adapted to be connected with the tire, sind fitting` having' a flanged boss on its crd, a rubl er air chamber having' an inwardly directed Harige at .i s lower end engaging said ilai'ig'ed boss, means (1o-acting with the foregoing' cle n'lents for measuring 'the expansion oi! said chamber, and means for holding' said ilal'ig'cd end oi" the air chamber tight against said boss.

in a pressure gag@ a fitting adapted to be connected with the tire7 said fittingn having' a flame-,cd boss on its end, a rubber air chan'iber 4l'utv-irng' an inwardly directed flange at its lower end boss7 ineens for measuring the expansion of said chambery. a split ring); encirclingn said flanged end oii the air chamber, said nieans including a continuous circiiilarcasing girdling'said split ring. l

In a pressure grapje, a fitting adapted to' be connected with `the tire, said fitting;1 'having a Banged, boss on its end, a rubber air chamber having' en inwardly directed flange et 'its lower end engaging said flanged boss,

engaging seid fiangcd i means for measuring the expansion of said chamber a split ring encircling the flanged end of the air chamber, another split ring encircling the first split ring and having a beveled edge, said measuring means includ-l the top of said air tube, forming a shoulder thereon, and a washer having inner straight sides adapted to register with the flattened sides of said air tubepand placed below said nut, and a Sleeve having a shoulder, the upper end of said sleeve adapted to be secured to said flanged lower end and said shoulder adapted to bear against the lower part of said washer, and an expansible air chamber secured to said boss.

8. In a pressure gage for tires comprising a tting, an expansible air chamber secured to said tting, means for securing the fitting to an inlet tube of a tire, said tube having flattened sides, said means comprising A,an annular nut secured to and near the top of said tube forming a shoulder thereon, a washer having inner straight sides adapted to register with the flattened sides of said air tube and placed below said nut, and a sleeve adapted to be secured to the lower end of said fitting, said sleeve having `an inner flange and the flange adapted to bear against the lower part of said washer.

9.- As a new article of manufacture, a rubber air chamber for pressure gages havving an end wall provided with a laterally extending cavity with a reduced outer opening, said air chamber having an opening at its opposite end.

10. In a pressure gage for tires, an expansible body, a casing surrounding said body, means for securing the casing to said body, a gage bar in contact with said body and protruding through said casing, compressible means for resisting the outward movement of the gage bar, a flexible collar attached to said casing where the gage bar projects, the collar surrounding the gage bar.

11. In a pressure gage, a rubber air chamber imperforate except at its inner end, a gage bar, means for detachably gripping the gage barv to said chamber at its outer end, a casing surrounding said chamber, means gage bar protruding through said casing,

and a coil spring around the gage bar within the casing, one end of the spring bearing againstthe end of the air chamber and the f other end bearing against the chamber.

12. In a pressure gage, a casing having a flanged bottom, a bod'y adapted to connect with the inlet tube of a tire, said body7 having a central boss and a flange, said flanged bottom registering with the ange of said body, and means for securing said flanges together, a rubber air chamber secured to said boss Within said casing, a gage bar, one end of said bar bearing on the outer end of the air chamber and the other end protruding through the outer end of said casing, compressible means for resisting outward movement of the gage bar.

13. In a pressure gage, a fitting adapted to be connected with a tire, a rubber air chamber imperforate except at its inner end, and having straight outer walls, the inner end of said chamber held in air-tight contact with the upper part of said fitting, by means of a split ring encirclin the outside portion of the inner end o said air chamber and a continuous circular member forced over said split ring, adapted to close it over the end of said chamber, and means lfoor measuring the expansion 'of said cham` 14. In a pressure gage, a casing, a fitting, a rubber air chamber inclosed in said casing, means for securing the inner end of said chamber to the fitting, means for securing the casing to the fitting, means for securin Vthe fitting to an inlet tube of a tire, a flange cap adapted to fit the outer end of said chamber whereby expansion of the outer end of said chamber is equalized, a retarding springy between said cap and casing, and means for measuring the expansion of said chamber.v

15. In pressure gages for pneumatic tires, a cylindrical rubber air chamber, having an opening in one end and the other end closed, a cap bearing on the closed end, means at the closed end for securing an indicator bar detachably thereto, a cylindrical casing with an opening in its outer end, said casing adapted to loosely surround the chamber and indicating bar, a coil spring surrounding the indicator bar and bearin between th air chamber and casing, said bar adapted t` protrude through the opening in said casing and directly show the air pressure, said chamber having wire below said cap surrounding its exterior side walls.

16. In pressure gages for pneumatic tires, a cylindrical casing having an opening n its outer end, a cylindrical rubber air chariiber within the casing having an opening in its inner end and the outer end closed, Wire 'surrounding the exterior side walls of said tor bar and inclosed in said casing and bearing between the air chamber and casing, said cap extending to the inside walls of said casing and coperating therewith whereby tire air chamber and indicator bar are guided to move parallel with said casing, the indicator bar adapted to protrude through said opening in the casing.

17. In a pressure gage, a cylindrical rubber air chamber having straight longitudinal Walls, an indicating bar, a cylindrical casing surrounding said casing. and bar, said indicating bar being at the outer end of said chamber and protruding through said easing, a recessed cap detachably secured to the outer end of said chamber, Wires surrounding said chamber below said cap, a coil spring surrounding said indicating bar, said spring seated on the top side of said cap and bearing against said casing.

18. In a pressure gage, a tubular rubber air chamber, said chamber of constant diall ameter open at one end and the other end closed, a body portion, means for securing said chamber at its open end to said body portion, a detachable recessed cap bearing against the closed end of said chamber, an indicator bar at the closed end of said chamber, a coil spring surrounding said bar and bearing against the air chamber and casing, a casing secured to said body portion, said bar adapted to protrude through the outer end of said casing, wire surrounding Vthe exterior Walls of said chamber below said cap, means for detachably securing said body portion to the inlet tube of a tire.

19. In a pressure gage, a rubber body portion, a metal body portion with an opening, means for securing said rubber body portion 'to the metal body portion in air tight engagement, means for securing the metal body portion to the inlet tube of a tire, said rubber body portion having a centrally located pocket in its top, an indicating bar with a iiange on one end, said flange and said pocket adapted to detachably t in close engagement with each other, and means for in asuring the expansion of said rubber body portion.

20. In a pressure gage, a rubber air chamber having an opening in one end and the other end being closed, means integral with the air chamber at the closed end for attaching a gage bar centrally thereto, means for resisting outward movementof the air chamber, a body having a boss on one end and a recess on the other end, said chamber secured at its open end to said boss, a casing attached to said body and surrounding said chamber, and means for securing' the body at its recess end to the inlet tube of a tire. I

Q1. In a pressure gage a longitudinally expansible rubber air chamber imperforate except at its inner end, the outer surface of the longitudinal walls of said chamber being of constant diameter and rings surrounding said air chamber, said rings being of uniform diameter and preventing lateral expansion of said walls, a gage bar operated by the end of the chamber, and means independent of said rings for opposing longitudinal expansion of the air chamber.

22. In pressure gages for tires, a body, a rubber air chamber having non-folding longitudinal walls and closed on one end, the other end open, a cap on the closed end, the chamber at its open end secured to said body, Wire surrounding said chamber, the Wire being below said cap, a gage bar at its inner end adapted to connect with said cap, a coil spring surrounding said bar and one end of the spring resting on the upper side of said cap, the other end bearing against the casing, a casing having an opening in its outer end, said casing surrounding said body, the outer end of the bar adapted to protrude through the opening in said cas ing, and means for securing the gage to the inlet tube of a tire. l

23. As a new article of manufacture a rubber air chamber for pressure gages, imperforate except for an opening in one end, the external wall being substantially cylindrical, and an abrupt internal flange at said end.

2d.V In air pressure gages for tires, a rubber air chamber, imperlorate except for an opening in one end, an internal flange at said end; said flange at its upper portion having an abrupt shoulder, and means exerting inward radial compression against the outer side wall of said lower end for securing the flange in air tight engagement withY other means for attaching the gage to the inlet tube of a tire.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 2d day of September, 1910.'

JUNIUS A. BOW'DEN. 

